Manways and covers are typically constructed from
aluminum, cast-iron, or a composite material such as
carbon-fiber.

They are designed to withstand the heavy loading of
transport vehicles and protect the spill containment bucket
and fill from dirt and debris.

They can either be an integral part of the spill containment
bucket, or they can be separate components such as the
type used for below-grade spill containment systems.

As can be seen from the lower image on the left the cover
is painted a color that represents the product stored in
the UST. This color must be in accordance with the
requirements of the API recommended practice RP 1637,
and COMM 10 code section 10.230(12)